This invention relates to a shearer drum for a mining machine used in underground mining and more particularly to controlling nozzles disposed on the periphery of the drum together with cutter picks by subdividing the nozzles into groups which extend substantially parallel to the rotational axis of the drum and providing that the groups of nozzles connected by controllable valves to a line-carrying high pressure liquid are controlled to discharge liquid only when disposed opposite the mine face.
In West German Patent Publication No. 3,202,315 there is disclosed a shearer drum having cutter picks on the drum periphery. The operation of the cutter picks is assisted by a stream of high-pressure liquid. In West German Patent Publication No. 3,009,771 there is disclosed high-pressure nozzles on the periphery of a cutter drum which are divided into discrete groups with each group of nozzles being supplied with high-pressure liquid by way of a valve and associated sections of a line when the nozzles of a group are directed toward a mine face. The various valves are actuated by means of a disk which is mounted for rotation around the drum axis and is connected to a clearing plate holder. The disk pivots with the plate holder and depending on the position into which the assembly is pivoted, only the nozzles disposed on one half of the drum periphery which is distant from the plate are connected to the lines supplying high-pressure liquid. European Patent Specification No. 0,010,534 discloses a control for a medium used for cool cutter picks of a shearing tool by means of an axially moveable pick stem or shank. The shank of the pick is resiliently supported against the cutting pressure. The shank of the pick can be displaced against a valve that is used to control the flow of coolant. Of these known disclosures, a system disclosed in German Patent Specification No. 3,009,771 provides that the nozzles in groups are supplied by way of a common valve for each group with high-pressure liquid only when the groups are aimed at the mine face. This is advantageous because it requires relatively few valves to connect only the nozzles on the drum which are directed to the mine face with the high-pressure line. However, an actuating or control disk and an element for actuating and moving the disk into a correct pivoted position is required.